import re

date = ['\n        \t       ', '\n\t    ', '\n                (2019)\n            ', '\n    \n\n    ', '\n    ', '\n\n    \n    \n            ', '\n        ', '\n    \t\n\t    \t', '\n        ', '\n\t\n    ', '\n\n            ', '\n    \n\t', '\n    ', '\n      \n']
print(re.findall(r'\d+', str(date))[0])